Josh Rubin

NPSY 12: Sensory Processes

November 21, 2000

Experiential Hearing Deprivation

For the Sensory Processes class, we were required to spend 8 waking hours wearing earplugs to mimic hearing loss and appreciate hearing's contributions to everyday life. This experience was very interesting, and I had several reactions to the experience of attenuated hearing, and would not like to repeat them.

While I was certainly able to carry on life as usual (albeit with some minor modification in behavior), it was not a pleasant experience to lose some ability to hear. Several of my experiences during the day are worth noting. One phenomenon immediately apparent was the fact that all sound entering my ears was attenuated. By inserting the earplugs, I had effectively induced conduction loss of hearing in myself. Conduction loss occurs when the outer or middle ear passages are blocked. These passages involve the transmission and amplification of sound into the inner ear mechanisms. The reason that the sound was diminished was partly due to the fact that the air molecules set into vibration from the sound source did not have sufficient ability to cause the pliable material of the earplugs to transmit the whole signal down their lengths. Normally, the air molecules cause the eardrums to vibrate directly; the change of media caused the sound waves to be absorbed before continuing on to the eardrums. If the earplugs were made of a stiff material that readily conducted sound, the sound would not have been diminished as much. Also, the resonant frequency of the auditory canals is around 3,000 Hz. Frequencies in this range are amplified before they vibrate the eardrum, making this the most sensitive frequency range of our hearing. By eliminating the ability of these frequencies to resonate in the auditory canals with earplugs, a decreased signal was sent to the eardrums.

A consequence of this decrease in hearing ability was my continual asking of people to repeat what they said. Fortunately, I was running errands around campus most of the day, so similar people weren‚t subjected to my requests for repetition. And speaking of people‚s speaking…I noticed, in conversation, that people‚s pronunciation of words seemed somehow „off.‰ After further attentive analysis, I found that certain consonants were diminished from their speech. After later consulting the textbook, I found that the consonants d, t, s, f and the „th‰ sound all fall in the 3,000 Hz range. After already knowing that this range is attenuated due to the earplugs, I came to the conclusion that the further lack of hearing in this range caused the „offness‰ of peoples‚ speech. As an aside, I also found that as the day progressed, I adapted to this and found myself not straining to understand peoples‚ speech as much.

Furthermore, I found from the outset that my own voice was strange sounding. I found that, at first, I was speaking much louder than usual when not concentrating on controlling the volume of my voice. Several of my companions noted this, and from then on, I had to consciously guesstimate about whether or not my speech volume was at an uncomfortable decibel level. This experience was due, of course, to the fact that the sound of my voice was conducted through the bones of my skull. Because bone conduction of sound has a threshold of about 30 dB higher than normal conduction through the ear, my own voice sounded softer. To compensate for this, I upped my speaking volume.

An additional reason why I would not like to lose my hearing (due to trauma or old age) would be music. I listen to music on a constant basis, and very much did not like going almost eight hours without hearing some of my favorite tunes. At one point, I cranked the volume on my stereo to alleviate this; however, my suitemates soon complained, and I was unfortunately unable to continue. (I would like to suggest at this point that the instructor invest in earplugs with tiny radio receivers, so that this horrible loss doesn‚t occur in future years.)

One last phenomenon occurred when I removed my earplugs. I climbed into my car around the 8-hour mark, and removed them because I didn‚t want to endanger my car (or myself). After starting the car, as usual, I began to hear a strange swishing noise. I reluctantly turned down the radio (which was heartbreaking…I had gone without for so long), and listened to the engine. After hearing the swishing in „drive,‰ I shifted to „park‰ and idled the engine. Motionless, I strained my ears; the car didn‚t make the noises. Shrugging, I resumed my forward motion. The alien swishing promptly returned. I almost turned the car around to point it in the direction of a garage when I realized that the swishing was, in fact, the rubbing of the arms of my jacket against my knees. Even with the realization of the source of the sound, it still sounded very strange for several moments. This was due, of course, to the fact that I had gone so long without hearing all the normal, everyday noises that we usually tune out. Because I had never consciously focused on the swishing of my jacket, it was a novel stimulus. Needless to say, I was quite glad there was nothing wrong with my car.